When it comes to measuring residential energy performance, few metrics carry as much weight as the HERS Index. The Home Energy Rating System (HERS) Index provides a standardized way to evaluate a home’s energy efficiency, giving builders, homeowners, and buyers a clear number that reflects how a home performs relative to a baseline. Whether you […]
Water vapor is invisible, odorless, and easy to overlook, yet it is one of the most consequential forces inside any building. The relationship between moisture sources, indoor humidity levels, and mold growth follows a surprisingly direct path. A small amount of additional water in the air can shift conditions from comfortable to problematic, especially in
When Marvin Windows and Doors announced its intent to pursue Passivhaus certification in 2013, it marked a turning point for North American builders aiming to meet the rigorous Passive Building standard. Until that point, obtaining certified high-performance windows meant either working with European manufacturers at premium prices and extended lead times, or relying on just
The push for higher energy performance in residential and commercial buildings has led to innovative regulatory approaches across the United States. One notable example is the Massachusetts stretch energy code, formally known as Appendix 120AA of the state building code. This amendment, approved by the Massachusetts Board of Building Regulations and Standards, gives individual municipalities
When the ENERGY STAR program released thermostat recommendations suggesting 78°F for summer cooling and 70°F for winter heating, the public response was swift and skeptical. Many homeowners found these temperatures unreasonable, preferring to crank the air conditioning down into the low 70s or sleep under heavy blankets while the AC runs nonstop. However, the real
Fresh indoor air is essential for healthy living, yet many affordable housing renovation projects overlook mechanical ventilation until late in the design process. The reality is that as we tighten existing homes through air sealing and insulation upgrades, we also reduce natural air leakage, which can trap moisture, odors, and airborne contaminants indoors. Controlling Indoor
If you don’t understand what a housewrap does and how it works, you are likely doing more harm than good to your building envelope. Placed beneath the siding, housewrap acts as a second layer of defense, protecting structural sheathing from moisture while allowing water vapor to escape. The range of quality housewrap materials has expanded
In the Roxbury neighborhood of Boston, a remarkable reconstruction project is proving that exceptional energy efficiency does not require a massive budget or a team of specialized consultants. The Pratt House, a modest 750-square-foot cottage originally built in 1850 as a gunsmith shop, is being rebuilt to achieve energy performance approaching the rigorous Passivhaus standard.
When selecting rigid insulation for high-performance building envelope assemblies, professionals must balance thermal efficiency, fire safety, moisture management, and environmental impact. Among the available options, phenolic foam insulation has emerged as a distinctive material that offers compelling performance characteristics. Kingspan Kooltherm, a phenolic foam rigid insulation product, has gained attention in the building science community
When a house has sheltered a family for decades, the kitchen often bears the heaviest wear. After raising four children and beginning to care for grandchildren, a Honolulu couple decided it was time to transform their cramped, dark kitchen into a space that would support them through retirement and beyond. They turned to architect Don
